Body worn apparatus

ABSTRACT

A method and apparatus provides a body worn apparatus having a plurality of activation elements arranged in at least one bundle, and a substrate supporting the plurality of activation elements. The method also places the body worn apparatus onto the body of a person, and activates the at least one bundle.

FIELD OF THE INVENTION

The present invention relates generally to actuators and, in at leastone embodiment, to such actuators that are hydraulic or fluid poweredand/or used as an artificial or “mechanical” muscle and used in a bodyworn apparatus.

BACKGROUND OF THE INVENTION

Actuators typically are mechanical devices that are used for moving orcontrolling a mechanism, system or the like and typically convert energyinto some type of motion. Examples of actuators can be found in anynumber of applications encountered in everyday life includingautomotive, aviation, construction, farming, factories, robots, healthcare and prosthetics, among other areas.

Mobile robotics and advanced prosthetics will likely play importantroles in the future of the human race. Actuators frequently are used inthese applications that enable movement of a robot or user arm or otherappendage or item as desired.

Most existing mobile robots and advanced prosthetics, however, lack thestrength and speed necessary to be effective. This is because theysuffer from poor specific power (strength×speed/weight) which determineshow quickly work can be done compared to another actuator of the sameweight.

For example, if such devices are capable of lifting significant weight,they must do so very slowly, which inhibits their adoption for mostapplications. On the other hand, devices that can move more quickly arejust not capable of handling anything more than the smallest weight.

Hydraulic and pneumatic power systems can be used with such actuators,among other power systems. Pneumatic power systems, however, have arelatively low operating pressure, which limits the amount of force theycan impart and exhibit poor controllability due to the compressiblenature of air, among other drawbacks.

Additionally, conventional hydraulics technology suffers from poorefficiency, noisy operation, high cost and maintenance challenges amongother problems. These and other problems inhibit the use of hydraulicsin many applications.

SUMMARY OF THE INVENTION

In accordance with one embodiment of the invention, a method andapparatus provides a body worn apparatus having a plurality ofactivation elements arranged in at least one bundle, and a substratesupporting the plurality of activation elements. The method also placesthe body worn apparatus onto the body of a person, and activates the atleast one bundle.

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed description will be better understood when readin conjunction with the appended drawings in which there is shown one ormore of the multiple embodiments of the present disclosure. It should beunderstood, however, that the various embodiments of the presentdisclosure are not limited to the precise arrangements andinstrumentalities shown in the drawings.

FIG. 1 is a plan view of one embodiment of an activation element of thepresent invention that may be utilized with the actuator of the presentinvention illustrated in a first “at rest” position;

FIG. 2 is a plan view of the element of FIG. 1 illustrated in a secondactivated position;

FIG. 3 is a partial plan view of one embodiment of the present inventionillustrating a plurality of activation elements arranged in a bundle;

FIG. 4 is a partial cross-sectional view of one embodiment of thepresent invention illustrating a plurality of activation elementsenclosed in an outer sheath member or the like;

FIG. 5 is a semi-schematic view of one embodiment of the presentinvention illustrating one potential use of the activation elements;

FIG. 6 is a table illustrating performance characteristics of humanmuscles and hydraulic systems; and

FIG. 7 is a graph illustrating contraction stress vs. tube diameter.

FIG. 8 is a schematic front view of a body worn apparatus configured inaccordance with illustrative embodiments of the invention.

FIG. 9 is a schematic rear view of the body worn apparatus of FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION

Various embodiments of the present invention are described below withreference to the accompanying drawings. It should be understood that thefollowing description is intended to describe exemplary embodiments ofthe invention, and not to limit the invention.

It is understood that the present invention is not limited to theparticular components, analysis techniques, etc. described herein, asthese may vary. It is also to be understood that the terminology usedherein is used for the purpose of describing particular embodimentsonly, and is not intended to limit the scope of the present invention.It must be noted that as used herein, the singular forms “a,” “an,” and“the” include plural reference unless the context clearly dictatesotherwise. The invention described herein is intended to describe one ormore preferred embodiments for implementing the invention shown anddescribed in the accompanying figures.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meanings as commonly understood by one of ordinary skillin the art to which this invention belongs. Preferred methods, systemcomponents, and materials are described, although any methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of the present invention.

Many modifications and variations may be made in the techniques andstructures described and illustrated herein without departing from thespirit and scope of the present invention. Accordingly, the techniquesand structures described and illustrated herein should be understood tobe illustrative only and not limiting upon the scope of the presentinvention. The scope of the present invention is defined by the claims,which includes known equivalents and unforeseeable equivalents at thetime of filing of this application

Various embodiments of the present invention are directed to variousdevices that are fluid powered, such as by hydraulics or pneumatics, forexample. It is to be understood, however, that some embodiments of thepresent invention are not limited to these two specific technologies.

In operating a robot, advanced prosthetic, or some other item ormechanism, some type of power system typically is provided to enableparticular movement, such as moving an arm or other appendage, forexample. As readily can be discerned, in order to provide at least upand down movement to an arm member or the like some type of mechanicalor other actuator typically is employed.

In a simple example, a piston driven actuator may be implemented toaccomplish this movement. By moving the piston back and forth within acylinder, the piston rod provides the basic movement to the arm memberconnected at is distal end.

Another type of actuator can be one that mimics the motion of a realbiological muscle in the body of a human or other animal. Theseartificial or mechanical muscles typically provide some type ofexpandable member or tube connected at one end to an arm member, such asa forearm of a robot, for example, and at the other end to anothermember such as the upper arm or shoulder of a robot, for example.

Briefly, in operation, when such a member is expanded in a directionsubstantially perpendicular to its longitudinal centerline, itessentially contracts the member thereby drawing the arm closer to theshoulder. When the member is thereafter allowed to expand in a directionsubstantially parallel to its longitudinal centerline, it essentiallyextends the member and the arm moves away from the shoulder.

One example of such a mechanical muscle is known as a McKibbons styleactuator, which is hereby incorporated by reference. It is to beunderstood, however, that the particular type of mechanical muscle andcorresponding expanding member can vary without departing from theteachings of various embodiments of the present invention.

These types of actuators or mechanical muscles exhibit a specific power(strength x speed/weight) that far exceeds that of existing actuatorstypically used in robots that suffer from poor efficiency, noisyoperation, high cost and maintenance challenges, among other drawbacks.These drawbacks and more are readily solved by the design ofillustrative embodiments of the present invention that readily exceedthe performance of real biological muscles.

Additionally, as the human race begins to work in close collaborationwith robots, advanced prosthetics, and similar machines and mechanisms,they are anticipated to expect the robots to be stronger, faster, havebetter endurance, be more precise, and cost less than other options.They also may expect robots to quickly and efficiently carry out theirassigned physical tasks with little or no down time for maintenance orfatigue, for example.

Biological muscles consist of many smaller “actuator” fibers calledsarcomeres, bundled in parallel. During movement of a body limb, forexample, all or just a partial subset of available fibers may beactivated depending on the task involved.

By scaling down the size of mechanical muscles, arranging them inbundles and designing them to handle much higher hydraulic pressures, alarge increase in specific power is achieved. Significant reduction inthe overall weight of this design, among other factors, leads to thisincrease in specific power. At the same time, by activating any numberof the actuators arranged in such a bundle to vary the power output forthe task at hand, significant power savings is achieved.

When employing these types of mechanical or artificial muscles, thetrend is to provide a single actuator for each direction of desiredmotion. With this design, variations in movement and control arelimited.

One key feature among many of illustrative embodiments is to provide aplurality of discrete, readily interchangeable mechanical muscles foreach direction of desired motion, where each muscle has a predeterminepower capability. This concept dramatically teaches away fromconventional thinking, provides a number of distinct and unexpectedresults and advantages in the art, and essentially revolutionizes thepotential applications possible.

As one example, by using a plurality or bundle of muscles, the number ofmuscles activated can vary depending on the power requirements of thetask at hand. One advantage of this novel design concept is powerconservation, which is particularly important with mobile robots as wellwith overall environmental concerns.

Another advantage is in the type and number of potential applicationsthat become available by using a bundle of muscles. With conventionalthinking being to merely increase the size of the actuator or muscle toincrease the power capability of the device, applications are limited tolarger and larger devices. In the design discussed herein, smaller andsmaller applications are possible since the actuators can be smaller andlighter, among other attributes.

Examples of various hydraulic systems and robotic applications where amechanical muscle may be employed can be found, for example, inapplicant's issued U.S. Pat. No. 7,348,747 filed Mar. 30, 2006, issuedU.S. Pat. No. 7,719,222 filed Mar. 24, 2008 and pending U.S. patentapplication Ser. No. 12/731,270 entitled “Task Flexibility forActuators” filed Mar. 25, 2010 and related co-pending applications, allof the disclosures of which are hereby incorporated by reference. It isto be understood, however, that the particular details of the hydraulicsystem itself, as well as the robot, vehicle, tool, heavy equipment,actuator, or other apparatus, can vary without departing from theteachings of various embodiments of the invention.

FIGS. 1 and 2 generally illustrate one embodiment of a mechanical muscle10 (i.e., an activation element) that may be employed in variousembodiments of the present invention. The particular size, shape,material and design of the muscle 10 can vary so long as it falls withinthe scope of the appended claims.

Briefly, in operation, FIG. 1 generally illustrates the muscle 10 in anextended or at-rest position where no fluid is provided to the interiorof the muscle 10. As FIG. 2 generally illustrates, when fluid isprovided to the interior of the muscle 10, the muscle 10 expands in adirection substantially perpendicular to its longitudinal centerline,essentially contracting the muscle 10, thereby shortening it length.Conversely, when fluid is essentially released from the interior of themuscle 10, the muscle 10 expands in a direction substantially parallelto its longitudinal centerline, thereby increasing its length.

As readily can be discerned and described in more detail below, if themuscle 10 is attached on opposite ends to other members, desiredmovement between the members can be achieved. Additionally, theparticular type, shape, material and design of the muscle 10 can bevaried to in turn vary the movement between the two members to which itis attached.

As FIG. 3 generally illustrates, the number of muscles 10 utilized canbe expanded to vary the performance of the muscle 10 as needed. Inparticular, by providing a number of muscles 10 in one or more bundles12 a corresponding increase in the lifting or movement capacity of themuscle 10 or bundle 12 can be accomplished.

Existing actuators for robot, prosthetics, and the like are heavy andlack the specific power necessary for effective designs. This limits thenumber, strength, and speed of each degree of freedom in a robot or thelike.

While the human body has over 600 individual skeletal muscles, the mostadvanced humanoid robots in existence today can afford only 50 or soconventional actuators and still end up weighing twice as much as ahuman, which can present a safety issue when working closely withhumans. To be truly capable and safe, robots and prosthetics need to bestronger, weigh less, and have many more degrees of freedom than currentsystems.

Pneumatic actuators or mechanical muscles are limited by theirrelatively low operating pressure of about 100 PSI and poorcontrollability due to the compressible nature of air, which isgenerally the working fluid in such pneumatic systems. By utilizing adesign incorporating hydraulically actuated actuators or mechanicalmuscles as described herein that are capable of operating at much higherpressures of about 3000 PSI, incredible increases in power are providedwhile increasing controllability.

As the goal of robotics aims to supplant human labor, human skeletalmuscle is an appropriate standard to beat. Muscles provide adaptive,integrated closed-loop positional control; energy absorption andstorage; and elastic strain to allow for deformation of tissue underloads. They are rapidly responsive and able to adjust spring and dampingfunctions for stiffness and compliance in stability, braking, and more.A viable artificial actuation approach should at least provide suchcomprehensive functionality; additionally such an approach should meetor exceed the set of performance metrics of human muscles and improveupon muscles' limited peak performance envelope.

As FIG. 6 illustrates, hydraulic mechanical muscles 10 outperform humanmuscle in power density, efficiency, stress vs. strain, frequency,control resolution, and will closely match human muscle in density, andvariable compliance ability. In addition, hydraulic mechanical muscleswill also achieve significant improvements in the state of the art interms of cost, manufacturability, flexibility in application, andscalability. As described earlier, the power density factor is animportant criterion that implies the simultaneous speed and strengthneeded for things like running and throwing.

While existing somewhat exotic actuator technologies may exceed anysingle actuator performance metric, they are unable to providecomparable overall performance. For example, piezoelectrics areunacceptably brittle; shape memory alloys (SMAs) have prohibitively slowresponse cycles due to a temperature-dependent actuation;magnetostrictors require constant, fragile magnetic fields at largescales.

Additionally, electroactive polymers (EAPs), require large andpotentially unsafe actuation voltages (>1 kV, typical) and consistentcurrent to maintain displacement, possibly making them unacceptablyinefficient while chemically-activated ionic versions do notconsistently sustain DC-induced displacement and have slow responsetimes. Additionally, EAPs have difficulty damping for low frequencyvibration and inaccurate position sensing capabilities due to inherentactuator flexibility. Since biological joints are analogous todirect-drive actuation and therefore largely backdrivable (i.e.resilient), the same forces acting upon an EAP actuator in a leg forexample will cause it to deform and perform unexpectedly. Most of all,these materials are prohibitively expensive and complicated tomanufacture.

More conventional existing actuators fail to replicate muscle-likeperformance for a number of reasons. Electromagnetic approaches lack anyreal scalability because of their need for expensive, high power,rare-earth magnets. Their highly specialized motor design precludes theforce output properties of muscle tissue.

Out of all available actuation techniques, pneumatic actuators,particularly of the “mechanical muscle” or McKibbens type describedabove appear to most closely match the force-velocity and force-lengthcharacteristics of human muscle. These pneumatic actuators exploit thehigh power density, light weight, and simplicity of fluid power, butprecise control of these systems is difficult because of thecompressibility of air and the inherent excessive compliance,hysteresis, nonlinearity, and insufficient contraction rates of rubberactuators.

In contrast, a hydraulic approach to mechanic al muscle fluid poweravoids these limitations while at the same time offering inherentadvantages for adjustable compliance, proportional force output, energyrecovery and efficiency, precise control, and scalability. This broadcomplement of properties makes hydraulics an excellent candidate forbiometric actuation.

In fact, the overall superior performance of hydraulics for vibrationdamping, actuation frequency, and volumetric power for compact designsin general applications are well known. Furthermore, since hydraulicsoperate on virtually the same principles as pneumatics, which performcomparably to natural muscle, they are similarly suitable for artificialmuscles if used in the right actuator design. As such, a new paradigm inactuator approach is provided in at least one embodiment of the presentinvention that leverages the superior power and controllability ofhydraulics with biophysical principles of movement.

One of the many significant benefits of a bundle of mechanical musclesapproach is that simultaneous activation of all of the bundled actuatorsbecomes unnecessary; rather, there is the potential to activate only theminimum of muscle fibers or actuators that are needed for the task.Benchtop tests demonstrated a 3 inch displacement for a strain of 70%.Maximum pulling force (before material failure) was approximately 95pounds at a pressure of nearly 1800 PSI. This bundle approach tomechanical muscles will achieve at least 10 times the specific power ofhuman muscle while achieving similar impedance control, and will bepractical for use in robotic systems. As this type of system isperfected, additional increases in specific power are anticipated.

Human muscle is comprised of both pennate (fibers aligned at an angle tothe muscle's long axis) and parallel-fibred muscles, each withfunctionally-specific mechanical features: pennate muscles act aroundjoints, rotating their angle to act as variable gears, whileparallel-fibered muscles are the workhorses (cf. biceps brachii orsoleus) of load-bearing movement. The mechanical advantage of a bundleof small or miniature McKibbons type actuators is similar: sincePascal's Law holds that increases in fluid pressure are distributedequally to all parts of a system, force increases proportionally withthe cross-sectional area of the actuator. Since it has been identifiedthat adjustable force output can be a function of increased actuatordiameter, using bundles or clusters of miniature McKibbons typeactuators can scale upward in cross-sectional area through the additionof more actuators; since the individual actuator size does not increase,tolerances for pressure and stress remain the same while force outputincreases.

In a cylindrical pressure vessel, like a McKibbons Actuator, the effectof hoop stress from fluid pressure dominates the tensile stress in theindividual fibers. It is established that

$\begin{matrix}{T = \frac{PDd}{2\;{\sin(\theta)}}} & (1)\end{matrix}$

where P, D, d, and θ are the fluid pressure, actuator tube innerdiameter, fiber diameter, and weave angle respectively. As expected, thehoop stress, and therefore the tension, increase as a function ofactuator diameter. The relationship for the peak contractile force (F)of a McKibbons style actuator can be expressed as:

$\begin{matrix}{F = {\frac{\pi}{4}D_{o}^{2}P\frac{1}{\sin^{2}(\theta)}( {{3\mspace{14mu}{\cos^{2}( \theta_{0} )}} - 1} )}} & (2)\end{matrix}$

where θ_(o) and D_(o) represent the weave angle and diameter of theactuator while at rest. For a given fiber, with diameter d and maxtensile stress σ_(t), and initial weave angle θ_(o) we can use Eqns. (1)and (2) to determine the maximum allowable fluid pressure as a functionof diameter D_(o).

$\begin{matrix}{T_{m\; a\; x} = {\frac{\pi}{4}\sigma_{t}d^{2}}} & (3)\end{matrix}$

$\begin{matrix}{P_{m\; a\; x} = {T_{{m\; a\; x}\;}\frac{\sin( \theta_{o} )}{2\; D\; d}}} & (4)\end{matrix}$

Substituting P_(m)ax into (2) allows for calculation of the peakcontractile force F_(max) as a function of diameter. Here, we considerthe bundle of McKibbons actuator or BoMA approach where a single, largeactuator can be replaced with multiple smaller actuators. By usingsmaller cylinders, a significantly higher fluid pressure can be used.Let t be the thickness of the actuator tube and fibers, so that theouter diameter of the actuator is D+t. Then, we can calculate the peakcontractile stress as,

$\begin{matrix}{\sigma_{m\; a\; x} = \frac{4\; F_{m\; a\; x}}{{\pi( {D + t} )}^{2}}} & (5)\end{matrix}$

Using sample system parameters for θ, d, and t, and the tensile strengthfor high strength polyethylene, FIG. 7 shows the peak contraction stressover a range of possible tube diameters. Note the peak near D=0.6 cm,which illustrates that the tube diameter at which the greatest forcedensity can be achieved. In a real system, cylinders can only be closepacked to overall density of 78%, so there is a slight advantage tousing a single McKibbons actuator. However, as seen in the figure, this22% difference is small when compared with the improvement in forcedensity from using multiple cylinders. When compared with a singleactuator with a 4 cm diameter, the BoMA approach with multiple 0.6 cmdiameter actuators more than doubles the potential force density.

Hydraulics also enables important advantages for replicating theprinciple of co-contraction in biarticulate, flexor/extensor musclegroups. Co-contraction has been shown to perform multiple functions inhumans and animals, including a reduction of variability in reachingmovements through increased stiffness produced by muscle activation androbustness to perturbations and an increase in joint impedance forgreater limb stability, the quick generation of torque, and compensationfor torque components orthogonal to desired trajectories.

In the BoMA approach, the stiffness inherent to the incompressiblehydraulic fluid allows for precise control of a manipulator or legthrough co-activation; for example, differences in simultaneous agonist(biceps brachii) contraction and antagonist (triceps brachii)contraction determine the position of the forearm. Isometric force canbe determined by summing antagonist muscle torques; stiffness and torquecan thus be controlled independently. This stiffness can be dynamicallyincreased or decreased according to task requirements; greater stiffnessallows for more precise control, while decreased stiffness enables morecompliance. Additionally, the parallel elastic element in musculatureacts as a lightly damped, non-linear spring which is the primary sourcefor the passive tension (i.e., compliance) under eccentric loads whichfacilitates the contractile element's return to resting length. Theelastic sheath of the fibers will provide some of this passive tension.

Hydraulics will inherently provide the remainder of damping using valveswith adjustable orifices to produce a damping force proportional to thespeed of movement. Since the biological tendon may contribute a greatportion of compliance and therefore affect stiffness during locomotion,elasticity should be adjustable. Such stiffness will need to becounterbalanced with sufficiently high-bandwidth active and passivecompliance to provide robustness to collisions and to maximize safetyaround humans. Thus, a key design characteristic of the BoMA approach isa range of compliance in both spring and damping characteristics.Approaches to compliance can be divided into two categories: passive andactive. Passive approaches use the natural characteristics of materialsto achieve spring and damping effects. Active compliance, on the otherhand, is achieved by moving the actuator in a way that mimics a desiredcompliance.

Previously developed active approaches, such as the Series-ElasticActuator use an actuator and tight control loop to mimic compliance ofpassive materials. In this approach, basic compliance is achievedthrough placement of spring between actuator and load; a linearpotentiometer used to measure the spring's length provides force sensingthat is combined with position sensors to facilitate rapid adjustmentsfor desired position, velocity, springiness and damping gains. Theseries-elastic principle can be implemented using a hydraulic actuatorthat features low impedance and backdriveability; accordingly, the BoMAapproach will be backdriveable.

For the BoMA approach, passive compliance is achieved through a numberof means, including: the natural elasticity of the contractile sheath ofthe BoMA fibers, which provides a small restoring force back to restinglength; through the elastic “tendons” arranged in series with the BoMAclusters, connecting them to the robot skeleton; through co-contractioncontrol policies using adjustable stiffness; and through scalableactuation of individual fibers within clusters, exploiting thecompliance of the surrounding unpressurized actuator material.

The actuators and mechanical muscles 10 described above can be used in awide variety of applications extending beyond traditional robotics. Forexample, in accordance with illustrative embodiments the invention, theabove described actuators or mechanical muscles 10 can be implemented aspart of a body worn apparatus 20 that performs one or more a pluralityof functions. Those functions can include, among other things, 1)enhancing the natural muscle strength of the human being (e.g., aso-called “muscle suit”), 2) assisting the human being in their normalbreathing (e.g., acting as a respirator and/or providing CPR), 3)massaging natural muscles of a living being (e.g., a human being), 4)providing dynamic back support, 5) cooling or warming a living being orinanimate object, and 6) use for military and firefighting applications.

To those ends, FIG. 8 schematically shows a person wearing a body wornapparatus 20 configured in accordance with illustrative embodiments ofthe invention. In a complementary fashion, FIG. 9 schematically shows abackside view of the same person and body worn apparatus 20. It shouldbe reiterated that these drawings are mere schematic representations andnot intended to imply that all embodiments are oriented and configuredas shown. Moreover, the body worn apparatus 20 also may be configured tobe worn by non-human users (e.g., a horse or a dog). Discussion withregard to a human being thus is for simplicity and not intended to limitall embodiments of the invention. Those skilled in the art thereforeshould consider these figures as a starting point for expanding variousoptions commensurate with the scope of the appended claims.

Among other things, the body worn apparatus 20 may take the form of awearable article. For example, the article may be in the form of agarment having one or several pieces (e.g., a shirt and pantscombination, or a single body suit), a member with some attachmentmechanism (e.g., straps with Velcro to secure the member to the user'sbody), or some other device configured to be worn by a living being.Despite the form it takes, the body worn apparatus 20 has some type ofthe substrate 21 for supporting and accurately positioning theactuators/mechanical muscles 10. As such, it should be sized andconfigured to be secured with a living being. When the wearable articletakes on the form of a garment, for example, the substrate 21 may beformed primarily from a flexible material, such as a composite materialhaving fabric and advanced materials for supporting the variousstructures. For example, in that case, the substrate 21 may include asleeve 22 or similar apparatus sized and oriented to receive the limb(e.g., arm or leg) of a living being (e.g., the arm of a human being).In fact, that type of body worn apparatus 20 also may have a mainportion sized and oriented to receive the torso of a person. Despite theform it takes, the substrate 21 should be sufficiently strong to supportits components, while not unduly limiting movement of the user.

Placement of the artificial muscles 10 typically dictates at least partof their intended function. To that end, FIGS. 8 and 9 schematicallyshow placement of some components, including artificial muscles 10, inaccordance with various embodiments the invention. As shown, the bodyworn apparatus 20 of those figures includes a single body suit havingmechanical muscles 10 positioned at specified locations across thesubstrate 21. These muscles 10, which preferably are bundled asdescribed above, may be considered as being formed in different groupsdepending upon the function. It should be noted, however, that althoughmuscle bundles 12 are discussed as being in “groups,” some groups mayhave a single muscle bundle 12 only. Accordingly, discussion of groupsof muscle bundles 12 is but one of a number of different embodiments ofthe invention.

A first group of muscles 10 (referred to a “first muscle group 24”)augments the natural muscle strength of the user. For example, thismuscle grouping may enable a user to perform an unlimited number ofchin-ups, or lift 2 to 3 times more weight than without the body wornapparatus 20. Accordingly, the bundles of muscles 10 (also referred toas “muscle bundles 12”) are positioned strategically near the user'smajor natural muscle groups. The embodiment shown in the figures showstwo of many such strategic locations; namely, across the elbow and kneejoints 26A and 26B. Specifically, the first muscle group 24 has musclebundles 12 that enhance the strength and ability of the user as theyhinge/pivot/rotate their elbow joint 26A and/or knee joint 26B.

It should be noted that when used with reference to a joint, the terms“pivot, “hinge,” and rotate” may be used herein generally synonymouslyas meaning “to move the joint in its normal manner of moving, such asits natural hinging motion.” For example, the user may be considered tomove or hinge or rotate or pivot the elbow joint 26A when moving thelower arm relative to the upper arm in a natural manner, such as bycurling a dumbbell.

To those end, as shown in FIG. 8, one set of muscle bundles 12 extendsacross the user's elbow joints 26 and, consequently, is referred to as“artificial biceps.” The body worn apparatus 20 further has appropriateanchor points to secure the artificial biceps in multiple locationsalong the arm region of the body worn apparatus 20. For example, Each ofthe artificial biceps muscles may be secured to the substrate 21 at itsend region, and at pre-specified locations across its length.

In a corresponding manner, FIG. 9 shows bundles of mechanical muscles 10positioned on the back side of the elbow joint 26A to augment the user'striceps (referred to herein for simplicity as “artificial triceps”).Like the artificial biceps, the body worn apparatus 20 has appropriateanchor points to secure the artificial triceps. Like natural humantriceps, artificial triceps effectively are configured torotate/hinge/pivot the arm about the elbow joint 26A in a direction thatis generally opposite to that of the biceps. These artificial biceps andartificial triceps are selectively actuated as described above to mostefficiently enhance the strength of the user about the elbow joint 26A.Stated another way, the artificial muscle bundles 12 may work alone(e.g., the artificial biceps alone), or in combination (e.g., theartificial biceps and artificial triceps cooperating) to perform adesired function.

The artificial muscle bundles 12 in the leg region of the body wornapparatus 20 are similarly anchored and coordinated to provide the sameor similar enhanced strength functionality as described above withregard to the artificial biceps and artificial triceps. Specifically,the muscle bundles 12 shown in FIGS. 8 and 9 in the leg region augmentthe user's natural muscle strength about the knee joint 26B. Of course,it should be reiterated that various embodiments position muscle bundles12 across various other joints or in other locations to enhance strengthin those regions. For example, artificial muscles 10 can be placedacross shoulder joints, wrist joints, finger joints, ankle joints, andacross the body core/general abdominal area. Accordingly, discussionprimarily of the elbow and knee joints 26A and 26B is for simplicityonly and not intended to limit various embodiments.

When used to augment strength, the body worn apparatus 20 can have anyof a wide variety of different applications. Among other applications,the body worn apparatus 20 can be used for military, law enforcement,construction, factory work, therapeutic, handicap assisting, and otherapplications, to name but a few.

As noted above, in addition to enhancing and augmenting the user'snatural strength, the body worn apparatus 20 also can assist the humanbeing in their normal breathing (e.g., acting as a respirator and/orproviding CPR). To that end, the substrate 21 supports a second group ofartificial muscle bundles 12 (referred to as “second muscle group 28”)in its chest region/portion as shown schematically in FIG. 8. Morespecifically, this second group 28 should be positioned to correspondwith the chest region of the user for assisting normal breathing. Whenneeded, the bundle of artificial muscles 10 in the chest regiontherefore may periodically actuate to assist the user's breathingprocesses. This can be a continuous, periodic actuation, configuredspecifically to assist breathing.

FIG. 9 shows yet another application, in which a third group ofartificial muscle bundles 12 (referred to as a “third muscle group 30”)are strategically positioned to massage specified natural muscle groupsof the user. This third group 30 is schematically shown in the back ofthe user, which is a very common area for massaging. Of course, musclebundles 12 may be in any of a number of other regions to provide amassage. For example, those additional regions may include the legs, thearms, shoulders, feet, hands, neck, and the torso, to name but a few.

The third muscle group 30 shown in FIG. 9 also may provide dynamic backsupport to the user. The substrate 21 therefore may position artificialmuscle bundles 12 in a back region to control substratestiffness/flexibility. For example, a person riding on a long car ridemay vary the lumbar support in that region of the body worn apparatus20. The level and amount of support may be changed automatically, ormanually. In fact, some of the artificial muscle bundles 12 used forother purposes (e.g., those discussed above with regard to massaging)can provide one or more functions, such as massaging, automaticbreathing support, and dynamic back support, among other things.

As described above, the artificial muscle bundles 12 are fluidactivated. For example, some of the artificial muscle bundles 12 may beactivated by directing a liquid, such as water, into and out of theindividual activation elements. The inventors discovered that ifpositioned and configured appropriately, in addition to controllingmuscle actuation, this fluid can assist in controlling the user'stemperature. For example, water used actuate the artificial muscles 10can be chilled and placed in close thermal contact with the user toreduce the risk that the user may overheat when in a hot environment(e.g., in a desert or in a burning building). As another example, thatsame water can also be heated to keep the user warm in a coldenvironment (e.g., during prolonged hikes in cold geographies).

To those ends, the body worn apparatus 20 may include a temperaturecontroller 32 having the logic and structure for selectively cooling andheating the fluid directed to and from the artificial muscle bundles 12via various fluid transport tubes and channels 34 formed on or in thesubstrate 21. Among other things, the temperature controller 32 may havedirect contact or noncontact heating and cooling mechanisms forcontrolling fluid temperature. Some embodiments may have heatingmechanisms and no cooling mechanisms. Other embodiments may have coolingmechanisms and no heating mechanisms. Still other embodiments may haveboth types of mechanisms.

The temperature controller 32 may be completely integrated on the bodyworn apparatus 20, or distributed between the body worn apparatus 20 andsome exterior component. The exterior component may be securable to thebody worn apparatus 20, or remain separate.

The tubes and channels 34 distributing the fluid (shown generally inFIGS. 8 and 9 merely as arrows) about the substrate 21 are strategicallypositioned to selectively contact the user in specific locations. Theymay take the most direct path to the artificial muscles 10, or take alonger path (e.g., in a sinusoidal path) to cool or heat more area ofthe user's body. The body contact of the tubes and channels 34 may bedirect to the user's skin, or may be through some other element, such asa thin layer of material protecting the user's skin from the anticipatedfluid temperatures.

This embodiment thus produces a heat transfer relationship between theuser and the fluid, which can improve operation of other functions. Forexample, when used to cool the user, such as in a firefightingapplication, coolant fluid returning to the temperature controller 32 iswarmer due to its cooling contact with the user. This warmer water maybe used to help other processes in a subsequent heat exchangerelationship.

All or portions of the body worn apparatus 20 can include a thermalinsulating material that is exterior to the artificial muscles 10. Forexample, the insulating material can assist in keeping heat near theuser, or assist in keeping the user cool. This material can be on theinterior, exterior, or both.

The body worn apparatus 20 also may be configured to protect the user'ssafety in situations where the risk of injury from fire is high. Amongothers, this may include situations such as firefighting, hazardousmaterial handling, and bomb defusing. To protect the user, some or allof the components of the body worn apparatus 20 can be formed from fireresistant/retardant material. For example, the body worn apparatus 20may have a layer of fire resistant material on its most exteriorsurface, covering the artificial material and other components. Suchmaterial may include any of those materials used in clothing or otherrelated applications and are commonly known in the art.

Accordingly, illustrative embodiments extend use of the artificialmuscles/activation elements 10 beyond robotics and into a body wornapparatus 20 that can have any of a variety of helpful functions. Thebody worn apparatus 20 can have all of the noted functions, one of thenoted functions, or some other combination of functions. For example,some embodiments may have the augmented strength function alone, whileother embodiments may have the augmented strength function, coolingfunction, and fire resistant function.

Although the description above contains many specific examples, theseshould not be construed as limiting the scope of the embodiments of thepresent disclosure but as merely providing illustrations of some of thepresently preferred embodiments of this disclosure. Thus, the scope ofthe embodiments of the disclosure should be determined by the appendedclaims and their legal equivalents, rather than by the examples given.

It will be appreciated by those skilled in the art that changes could bemade to the embodiments described above without departing from the broadinventive concept thereof. It is understood, therefore, that thisdisclosure is not limited to the particular embodiments disclosed, butit is intended to cover modifications within the spirit and scope of theembodiments of the present disclosure.

I claim:
 1. A method of assisting a living being with an apparatussubstantially in the form of a wearable garment, comprising: providing asubstantially soft, pliable apparatus to be worn by an individual, theapparatus including a plurality of elongate, pliable, artificial musclestyle, incompressible hydraulic fluid activation elements arranged in atleast one bundle of activation elements, the activation elements beingarranged parallel in side-by-side relationship with respect to theirlengths, the elongate activation elements having a diameter between0.4-0.8 cm so that the bundle of activation elements has about twice theforce density of a single activation element having a diameter at leastfive times greater than the activation elements in the bundle; providinga substantially soft, pliable substrate for mounting of the at least onebundle of activation elements to likewise be worn by an individual andfor cooperative engagement with a body portion of an individual;providing an incompressible hydraulic fluid pump system for independentand selective activation of each activation element of the bundle tovary a force applied by the bundle and the substrate to the individual;anchoring both ends of each activation element of the bundle to thesubstrate so that when activated by the hydraulic fluid pump system adesired number of activation elements expand outwardly along theirlengths to thereby contract and provide a contraction force to thesubstrate; and activating a desired number of activation elements toprovide the force to the individual.